<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>【鼠标拖拽事件】</title>
    <style rel="stylesheet" type="text/css">
        div{
            height: 400px;
            width: 300px;
            background-color: aqua;
            position: absolute;
            left: 40%;
            top: 40%;
        }
    </style>
</head>
<body>
<div>

</div>
</body>
</html>